Self-sealing container closure

ABSTRACT

A sealing closure for dispensing fluid includes a closure body. The closure body has an attachment portion configured to attach to a container containing fluid, a dispensing portion, and a conduit connecting the attachment portion and dispensing portion and configured to direct fluid from the attachment portion to the dispensing portion. The sealing closure further includes a spring lid attached to the dispensing portion. The spring lid has a first portion coupled to the closure body, a second portion not attached to the closure body. The second portion is configured to contact the closure body when a pressure of the fluid is below a threshold, and flex to separate from the closure body when the pressure of the fluid meets or exceeds the threshold to create an opening for dispensing the fluid.

BACKGROUND

Self-sealing closures for containers made of flexible materials areknown in the art. The closures commonly have a flexible valve that isopened when a squeeze force is applied to the container creating apressure that exceeds a threshold. This squeeze to open configuration isconvenient as it allows consumers to dispense products with one hand andremoves the step of opening and closing a cap. There are many examplesof valves used in self-sealing closures. U.S. Pat. No. 4,988,016 toHawkins describes a valve created from two sheets of flexible materialheat welded together to form a channel. Squeezing the flexible packagecauses the channel to open into an ellipse shape allowing passage of theproduct from the container. Although this may be a low cost seal it isnot a particularly effective seal as it may leak or allow the contentsto be exposed to the outside environment. U.S. Pat. No. 6,050,435 toRandall G. Bush et al., describes a silicon seal with a slit that isopened by applying a squeeze force to the container. A slit in aflexible gasket is not ideal as it restricts the flow rate particularlyfor viscous fluids such as pastes and creams. Attempts to increase theflow rate, by increasing the size of the opening or varying the hardnessof the elastomer reduce the effectiveness of the seal. U.S. Pat. No.6,079,594 to Brown et al. describes a self-sealing closure having amarginal flange and a head portion with an orifice extendingtherethrough, which opens to permit fluid flow therethrough in responseto pressure. This has the disadvantage of complexity and is not suitablefor low cost applications.

SUMMARY

A low cost, highly reliable self-closing airtight seal is needed.

To this end, embodiments of the present disclosure include a sealingclosure for dispensing fluid. The sealing closure includes a closurebody. The closure body has an attachment portion configured to attach toa container containing fluid, a dispensing portion, and a conduitconnecting the attachment portion and dispensing portion and configuredto direct fluid from the attachment portion to the dispensing portion.The sealing closure further includes a spring lid attached to thedispensing portion. The spring lid has a first portion coupled to theclosure body, a second portion not attached to the closure body. Thesecond portion is configured to contact the closure body when a pressureof the fluid is below a threshold, and flex to separate from the closurebody when the pressure of the fluid meets or exceeds the threshold tocreate an opening for dispensing the fluid.

In some embodiments, the sealing enclosure includes a flexible seal onthe dispensing portion of the closure body, the flexible seal beingconfigured to contact the second portion of the spring lid when thepressure of the fluid is below the threshold. In some embodiments, theflexible seal is composed of thermoplastic elastomer (TPE). In someembodiments, the sealing enclosure includes a first part of the flexibleseal that is attached to the second portion of the spring lid, and isconfigured to contact the second portion of the spring lid when itflexes to separate from the closure body when the pressure of the fluidmeets or exceeds the threshold, and a second part of the flexible sealthat is not attached to the second portion of the spring lid and createsthe opening when the second portion of the spring lid flexes to separatefrom the closure body when the pressure of the fluid meets or exceedsthe threshold. In some embodiments, the spring lid is composed ofaluminum. In some embodiments, the sealing enclosure includes a chamberat the dispensing portion of the closure body, and a rim surrounding thechamber that contacts the spring lid. In some embodiments, the rim iscomposed of polypropylene. In some embodiments, the spring lid has alayer of polypropylene on a side configured to contact the rim, thelayer of polypropylene coupling the spring lid to the rim in the firstportion. In some embodiments, pressure that meets or exceeds thethreshold can be generated by a human hand squeezing a containerattached to the sealing closure.

Some embodiments include a fluid vessel comprising: the sealing closurecoupled to the container containing the fluid. In some embodiments, thesealing closure is coupled to the container by threads in the conduit.In some embodiments, the sealing closure is welded to the container. Insome embodiments, the sealing closure is riveted to the container.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective drawing of a self-sealing closure according toan embodiment.

FIG. 2 is a perspective drawing of a self-sealing closure according toan embodiment.

FIG. 3 is a perspective drawing of a self-sealing closure according toan embodiment.

FIG. 4 is a perspective drawing of a self-sealing closure according toan embodiment, attached to a fluid container.

DETAILED DESCRIPTION OF EMBODIMENTS

The present disclosure describes various embodiments of closures havinga flexible valve that is closed below a threshold squeeze force appliedto the container. Reducing the volume of the container by squeezing,results in achieving a sufficient pressure buildup that enablesdispensing of a product (i.e. a pressure threshold). The fluent productin the various embodiments may be contained in a plastic or aluminumtube, a flexible standup package or the like that is able to be squeezed(i.e. a container). The container may be configured to screw onto athread or may be riveted, glued, co-molded etc. to the sealing closure.

The sealing closure includes a chamber, seal, and spring lid. Varyingthe dimensions of the chamber, seal and spring lid allow an infiniterange of flow rates and required squeeze forces, without jeopardizingthe integrity of the seal. In some embodiments, the squeeze forces toopen the valve can be generated by a human hand squeezing the containerof fluid. Embodiments of the seal provide a barrier able to withstandatmospheric moisture (75% relative humidity at 30° C.) for 3 months.This would prevent the container contents either drying out or becomingdamp for this period, whilst also allowing easy dispensing.

In one embodiment the sealing closure is configured to screw onto athread which is integrated into a container. The closure body may bemanufactured from polypropylene and co-molded with thermoplasticelastomer (TPE) which is located in at least one part of the rim of achamber of the closure body. A leaf spring composed of spring aluminum(or other metal) with a coating of polypropylene (or other polymer) onone side is heat welded in place over the chamber exit. A thin film islaid on the TPE to prevent the TPE welding to the lid in the exit area.The film can be a dissimilar polymer that does not weld topolypropylene. This protective film is removed after the heat weldingstep. During welding the lid is welded around the chamber opening whichincludes a portion of the TPE either side of the opening. This improvesthe seal and prevents escape of the product during dispensing. Theresultant opening creates a single stream, which improves the dispensingand the ability of the seal to shut off the flow of product when itcloses. In other embodiments, the opening is configured to providemultiple streams.

FIG. 1 shows a self-sealing closure according to one embodiment. Theclosure comprises a chamber 1 with rim 1 a and thread 1 b. A section ofthe opening to chamber 1 is lined with flexible TPE seal 3. The closureincorporating the chamber is configured to screw onto a flexiblecontainer. Spring lid 2 is shown before welding over the opening ofchamber 1. Surface 1 a depicts the rim of the chamber to which a firstportion of lid 2 is welded. In this example surface 1 a ispolypropylene. The underside of spring lid 2 is coated withpolypropylene. When the first portion of spring lid 2 is welded intoposition a protective non-welding film is placed over a portion of TPE3. The film defines the opening as this area under the protective filmwill not be welded. The sections of TPE 3 that are adjacent to the exitare welded to the underside of the spring lid. Material dispensed fromthe closure in this example exits at right angles to the thread 1 b.

Thread 1 b can be used to attach the closure to a container containingthe fluid (see FIG. 4 ). In other words, thread 1 b can engage threadson the container to couple the closure to the container in a sealingmanner.

When the fluid is not under pressure, the second portion of lid 2 thatis not attached to the closure body rests in contact with the closurebody or the seal 3. When resting in contact with seal 3, the spring lid2 forms a sealing contact with seal 3. This sealing contact preventsingress or egress of atmospheric gases and moisture, or the containedfluid.

FIG. 2 depicts an embodiment of the closure configured to dispenseproduct in line with the thread. Lid 2 is shown in an open position.Product under pressure (not shown) lifts the spring lid 2 where it isnot welded to the closure (e.g. the polypropylene rim 1 a) at thechamber exit 8. TPE welded to lid 2 at position 4 adjacent the chamberexit stretches allowing the spring lid to flex open, when the thresholdpressure is applied to the container/fluid. TPE at the chamber exit 8 isnot welded to the lid due to the presence of temporary film between theTPE and lid during welding. Pivot point 5 is created during opening, andrepresents a boundary between where lid 2 is welded to the closure body7 and not welded to the closure body 7.

FIG. 2 shows a dispensing configuration of the sealing closure, whenfluid is under pressure meeting or exceeding the threshold, and beingdispensed. In this situation, the second portion of the lid 2 flexesaway from the closure body 7 and seal 3, creating an opening allowingthe fluid to flow out of the container.

In some embodiments, the opening is configured to open to apredetermined size for a variety of pressures. In other embodiments, theopening is configured to expand to a greater size in proportion to theapplied pressure, to accommodate variable flow rates. Moreover, the sizeof the opening can be adjusted depending on the viscosity of the fluidproduct to be dispensed, and the generally desired amount needed peruse. For example, a container of sunscreen may have a larger opening forlarge volume dispensation of the product, whereas an ointment containermay have a smaller opening for dispensing a small portion. Similarly, anopening for toothpaste may be larger (even given the smaller amountneeded) because the large opening facilitates a reasonable flow speedwith the high viscosity of the fluid.

The closure can also be configured to open in response to differentpressures depending on the target user. For example, in a container foroperation by a toddler or child, the pressure threshold for dispensingfluid may be lower than a container for operation by an adult.Similarly, in a container for operation by an elderly or arthriticperson, the pressure threshold may be lower than a container foroperation by a healthy adult.

FIG. 3 shows a threaded conduit 12 used to attach closure body 7 to aflexible container such as a plastic or aluminum tube. Lid 2 is shownwelded in position to the rim of the chamber which includes a section ofTPE at positions 4 and 9. In FIG. 3 , the sealing contact between lid 2and closure body 7 is shown.

FIG. 4 is a perspective drawing of a self-sealing closure according toan embodiment, attached to a fluid container 10. In the embodiments ofFIGS. 1-3 , the closure body 7 is coupled to the fluid container 10 bythreads 1 b inside threaded conduit 12, which engage counterpart threadson the closure body 7. In other embodiments, the closure body 7 issealingly attached to the fluid container 10 by welding or riveting. Thecontainer 10 may be a plastic or aluminum tube, a flexible standuppackage or the like that is able to be squeezed (i.e. a container).

Although the invention has been described with reference to embodimentsherein, those embodiments do not limit the scope of the invention.Modifications to those embodiments or different embodiments may fallwithin the scope of the invention.

What is claimed is:
 1. A sealing closure for dispensing fluid, thesealing closure comprising: a closure body having: an attachment portionconfigured to attach to a container containing fluid; a dispensingportion; and a conduit connecting the attachment portion and dispensingportion and configured to direct fluid from the attachment portion tothe dispensing portion; a spring lid attached to the dispensing portion,the spring lid having: a first portion coupled to the closure body; anda second portion not attached to the closure body, the second portionbeing configured to contact the closure body when a pressure of thefluid is below a threshold, and flex to separate from the closure bodywhen the pressure of the fluid meets or exceeds the threshold to createan opening for dispensing the fluid.
 2. The sealing closure of claim 1,further comprising: a flexible seal on the dispensing portion of theclosure body, the flexible seal being configured to contact the secondportion of the spring lid when the pressure of the fluid is below thethreshold.
 3. The sealing closure of claim 2, wherein the flexible sealis composed of thermoplastic elastomer (TPE).
 4. The sealing closure ofclaim 2, further comprising: a first part of the flexible seal that isattached to the second portion of the spring lid, and is configured tocontact the second portion of the spring lid when it flexes to separatefrom the closure body when the pressure of the fluid meets or exceedsthe threshold; and a second part of the flexible seal that is notattached to the second portion of the spring lid and creates the openingwhen the second portion of the spring lid flexes to separate from theclosure body when the pressure of the fluid meets or exceeds thethreshold.
 5. The sealing closure of claim 1, wherein the spring lid iscomposed of aluminum.
 6. The sealing closure of claim 1, furthercomprising: a chamber at the dispensing portion of the closure body; anda rim surrounding the chamber that contacts the spring lid.
 7. Thesealing closure of claim 6, wherein the rim is composed ofpolypropylene.
 8. The sealing closure of claim 7, wherein the spring lidhas a layer of polypropylene on a side configured to contact the rim,the layer of polypropylene coupling the spring lid to the rim in thefirst portion.
 9. The sealing closure of claim 8, wherein pressure thatmeets or exceeds the threshold can be generated by a human handsqueezing a container attached to the sealing closure.
 10. A fluidvessel comprising: the sealing closure of claim 1 coupled to thecontainer containing the fluid.
 11. The fluid vessel of claim 10,wherein the sealing closure is coupled to the container by threads inthe conduit.
 12. The fluid vessel of claim 10, wherein the sealingclosure is welded to the container.
 13. The fluid vessel of claim 10,wherein the sealing closure is riveted to the container.